1. Field of the Invention
The present invention relates to a refrigerator, and more particularly to a refrigerator having a refrigeration system which can improve a cooling efficiency.
2. Description of the Prior Art
Generally, a refrigerator is an apparatus for storing various foodstuffs in either a frozen or a refrigerated condition to extend the freshness of the foodstuffs for a long time. Such a refrigerator includes a compressor which circulates a refrigerant by compressing the refrigerant, a condenser for condensing the refrigerant to a liquid phase, and an evaporator for generating a chilled air by evaporating the liquid phase refrigerant.
The refrigerator has a freezing chamber for storing frozen foods such as meats or an ice cream, and a refrigerating chamber for storing foods at a relatively lower temperature. The chilled air generated by the evaporator is introduced into the refrigerating and freezing chambers by a fan.
FIG. 1 shows a conventional refrigerator 100. As shown in FIG. 1, refrigerator 100 has a refrigerating chamber 2 which is separated from a freezing chamber 1 by a partition wall 3. An evaporator 4 is installed in an evaporator chamber 7 which is formed at a rear portion of freezing chamber 1, and a compressor 6 is installed below refrigerating chamber 2. A condenser (not shown) is disposed between evaporator 4 and compressor 6.
Compressor 6 compresses the refrigerant to a high-pressure and high-temperature refrigerant, and the condenser makes a liquid-phase temperature by discharging a heat from the high-pressure and high-temperature refrigerant. The liquid phase refrigerant is supplied to evaporator 4 and is evaporated by evaporator 4, thereby generating the chilled air. In addition, a heater 9 is installed below evaporator 4 so as to defrost a frost adhering to evaporator 4.
Installed above evaporator 4 is a fan 5 for blowing an air toward evaporator 250. Fan 5 circulates the chilled air into freezing chamber 1 through a first chilled air inlet 41 formed at a rear wall of freezing chamber 1. In addition, some of the chilled air is introduced into refrigerating chamber 2 through a chilled air duct 45 formed at a rear portion of evaporator chamber 7 and through a second chilled air inlet 42 which is formed at a rear wall of refrigerating chamber 2. The chilled air which has been introduced into freezing and refrigerating chambers 1 and 2 is re-circulated into evaporator chamber 7 through first and second chilled air return passages 43 and 44 which are formed at a lower portion of freezing chamber 1 and at an upper portion of refrigerating chamber 2, respectively.
FIG. 2 is an enlarged view of evaporator 4 shown in FIG. 1. As shown in FIG. 2, evaporator 4 includes a bending pipe 46 and heat-exchange plates 47 which are attached to an upper portion of bending pipe 46.
The refrigerant supplied into bending pipe 46 is evaporated therein, thereby absorbing a heat from a periphery thereof. Accordingly, the chilled air is created at the periphery of evaporator 4. At this time, a heat-exchange area between evaporator 4 and the air is increased by heat-exchange plates 47 so that heat-exchange efficiency is improved.
However, in conventional refrigerator 100, a flow direction of the chilled air is constantly formed along the longitudinal direction of plates 47, so the chilled air does not widely make contact with a periphery air, thereby lowering the heat-exchange efficiency.
In other words, the air blown by fan 5 toward evaporator 4 flows in the longitudinal direction of evaporator chamber 7 due to plates 47, so the air does not uniformly make contact with bending pipe 46, so the heat-exchange efficiency between the air and evaporator 4 is reduced.
In order to overcome the above problem, various types of evaporators for improving the heat-exchange efficiency have been suggested, but they have presented problems.
For example, U.S. Pat. No. 5,241,838 issued to Kennedy discloses a refrigeration device which can improve the heat-exchange efficiency. Kennedy's refrigeration device comprises a spine fin which is disposed around a refrigerant pipe and makes a heat-exchange relationship with the refrigerant pipe.
However, since a fan is disposed above an evaporator in Kennedy's refrigeration device, an air blown by the fan does not widely make contact with the evaporator, so the heat-exchange efficiency is relatively reduced.